A woman shops for a fur coat at Bergdorf Goodman in New York City. Her Chinese pug, Miss Puffet, sits on a nearby chaise. December 1964. This is a previously unpublished image.Photograph by Albert Moldvay, National Geographic

We dubbed this setting the “Known World,” to imply there was more out there yet to be discovered, because we didn’t want to paint ourselves into a corner. It was our intention to use the Known World in ongoing open-ended campaigns run by multiple DMs, in which player characters could go back and forth from one DM’s game to another. Moldvay and I were already running our own campaigns this way, and we hoped to bring other DMs on board as well, so we’d all be playing in the same giant sandbox.